The present invention relates to a package for a pourable material and, more particularly, to a dispensing package which comprises a bottle, a pour-back spout and a closure. The present invention also relates to the features and aspects of the individual elements of the dispensing package, that is, to the features and aspects of the bottle, the pour-back spout and the closure.
Numerous types and styles of bottles for holding pourable materials are well known. Bottles made of polyethylene or other plastic or polymeric materials which are formed by blow-molding are commonly used as containers for soaps, detergents, bleaches, other laundry products, various foodstuffs and other liquid and particulate materials. In blow-molding, a heated, deformable body or cylindrical tube of unsolidified, plastic or polymer is extruded around an end of a hollow member or blow pin which extends into the body. Air or other gas may be blown or injected through the blow pin. The still deformable body is placed within an openable cavity mold having an interior contour which mirrors that of the exterior of the final product.
After the deformable body is located within the mold, air is blown or injected through the blow pin into the interior of the deformable body to expand it like a balloon. As the deformable body expands outwardly, it comes into contact with the interior of the mold. Further expansion and the on-going positive pressure within the now hollow interior of the plastic or polymer body force the still heated plastic or polymer against the interior of the mold. This results in the now expanded body assuming a shape complementary to the mold's interior. The plastic or polymer may cool to a selected degree due to its contact with the mold, which may be maintained at a predetermined temperature. When the plastic or polymer reaches a sufficient degree of coolness, it becomes sufficiently solidified or set into a configuration, in which its exterior contour permanently assumes the shape of the mold. The mold is then opened to permit removal of the molded product and the blow pin is removed from the product's interior. Removal of excess material adhering to the molded product, especially at the former point of entry of the blow pin may require cutting or trimming thereof from the product.
As is well known, the above procedure may be utilized to produce a bottle. The top portion of the bottle, often closable with a threaded closure or cp, has an opening through which material held in the bottle is pourable. This top portion is often referred to as a "neck finish."
The mold may be formed so as to produce a final product or bottle and a neck finish having various complex shapes. For example, the exterior of the neck finish may have formed thereon integral threads, as well as undercut areas, which result from the action of appropriately configured areas of the openable mold. Undercuts may be formed on the exterior of the neck finish due to the fact that the mold is opened away from the product's exterior upon its assuming its final configuration.
Undercuts are, however, typically avoided on the interior surface of the neck finish. This is so because the blow pin is typically not collapsable away from the interior surface. Withdrawal of the blow pin from the neck finish would cause exterior protruding portions of the blow pin about which the undercuts were formed to deform or distort non-undercut, smaller diameter portions of the interior of the neck finish. Such deformation is generally thought to be undesirable.
A wide variety of pouring spouts for the above type of bottle are also well known. In some cases bottles with integral spouts may be formed by blow-molding. Typically, however, pouring spouts are formed separately from their associated bottles and are thereafter mounted to the exterior or interior of the neck finish in numerous ways. Usually, non-integral pouring spouts are molded from polyethylene or other plastic or polymer. These spouts may be mounted to neck finishes by snapping or threading together mating portions on the spouts and the neck finishes, by adhering the spouts to the neck finishes, or by other techniques. Primary concerns of packaging manufacturers are the expedient, inexpensive production of bottles and spouts and the expedient, inexpensive attachment of the spouts to the bottles. A further concern is that the attachment of the spouts to the bottles retain integrity and remain essentially leak-proof to minimize spillage and leakage during shipment and during use by consumers.
A known type of pouring spout is a so-called pour-back spout. Pour-back spouts generally include an elongated nozzle or funnel having a pouring lip at one end. The exterior of the other end of the nozzle is connected to a web or floor which is, in turn, connected to the interior of a cylinder which surrounds and extends above the lower portion of the nozzle. Formed through the web or floor is a drain hole which is located diametrically opposite the pouring lip. Poured material which drips down the lip and the exterior of the nozzle is caught by the web and directed to the drain hole whereat it returns to the bottle. The surrounding of the funnel by the cylinder prevents dripping material from reaching the exterior of the neck finish and the bottle, while the web and the drain hole obviate wasting of the material.
Typical closures for the foregoing bottles and spouts may constitute molded polypropylene or other plastic screw caps, which may be threaded onto and off the neck finish and which surround and enclose the pouring spout when so threaded on. It is common for such caps to include facilities which seal against the spout or the neck finish when the cap is threaded on. Such sealing prevents the material within the bottle from reaching the threaded cap/neck finish interface to limit leakage.